What are the chances of me going overdue with me being a first time mum? Does is change the chances if I was born early, 9 days to be exact?

I'm currently 38 weeks 3 days so I have 11 days left until my due date. I've had no braxton hicks, no bloody show, no nothing! I don't even feel pregnant anymore and haven't for around 4 weeks

I just really don't want to go over and for her to come Christmas day and have to have her birthday on Christmas 😓

I've added two photos, first one is off today and the second is off a few days ago (same pyjamas as they're my comfy pants 😂)